[A Reversible Case of Korsakoff Syndrome in an Alcohol Dependent Patient]. / Der interessante klinische Fall ­ reversibles amnestisches Syndrom bei einem Patienten mit Alkoholabhängigkeit.

Alcohol dependent patients represent a high-risk group for vitamin deficiency, which could lead to variable cognitive dysfunctions and, as an extreme example, to an amnestic-confabulatory syndrome. In this case report, we report about an alcohol dependent 58-year-old patient without focal neurological symptoms with an amnestic-confabulatory syndrome. After substitution of thiamine, vitamin B12 and folic acid, cognitive symptoms completely vanish within a 22-month period of observation.

5-HT3 receptor influences the washing phenotype and visual organization in obsessive-compulsive disorder supporting 5-HT3 receptor antagonists as novel treatment option.

A role of the HTR3A-E genes in obsessive-compulsive disorder (OCD) can be expected based on promising effects of 5-HT3 receptor antagonists as adjunctive treatment of OCD. We therefore genotyped six common coding or promoter variants within the HTR3A-E genes in a case-control-sample consisting of N=236 OCD patients and N=310 control subjects and in N=58 parent-child-trios. Given the heterogeneous OCD phenotype, we also investigated OCD symptom dimensions and cognitive endophenotypes in subsamples. OCD patients scoring high for the washing subtype were significantly more likely to carry the c.256G-allele of the HTR3E variant rs7627615 (p=0.0001) as compared to OCD patients low for this symptom dimension. Visual organization was impaired in OCD patients and unaffected relatives as compared to healthy control subjects and carriers of the HTR3E c.256G/c.256G-genotype performed significantly worse (p=0.007). The case-control analyses revealed a nominal significant association of the HTR3D variant rs1000592 (p.H52R) with OCD (p=0.029) which was also evident after combination of the case-control and the trio-results (p=0.024). In male subjects, the variant rs6766410 (p.N163K) located in the HTR3C was significantly associated with OCD (p=0.007). The association findings of the HTR3C and the HTR3E remained significant after correction for the number of variants investigated. These findings indicate a role of common variants of the HTR3A-E genes in OCD and OCD-related phenotypes and further support the use of 5-HT3 receptor antagonists as novel treatment options. The HTR3E gene is a novel candidate gene impacting on the individual expression of OC symptoms and OCD-related cognitive dysfunction.

The functional coding variant Asn107Ile of the neuropeptide S receptor gene (NPSR1) influences age at onset of obsessive-compulsive disorder.

Neuropeptide S (NPS) is a novel central acting neuropeptide that modulates several brain functions. NPS has shown strong anxiolytic-like effects and interactions with other central transmitter systems, including serotonin and glutamate. A coding variation (Asn107Ile) of the NPS receptor gene (NPSR1) was associated with panic disorder and schizophrenia. Based on these encouraging findings, the present study aimed at exploring a potential role of NPSR1 in obsessive­compulsive disorder (OCD). A sample of 232 OCD patients was successfully genotyped for the NPSR1 Asn107Ile variant (rs324981). Age at onset was taken into account to address the heterogeneity of the OCD phenotype. The NPSR1 genotype significantly affected age at onset of the OCD patients, with a mean age at onset approximately 4 yr earlier in homozygous carriers of the low-functioning Asn107 variant compared to patients with at least one Ile107 variant (p=0.032). Case­control analyses with 308 healthy control subjects reveal a highly significant association of the Asn107 variant with early onset OCD (odds ratio=2.36, p=0.0004) while late onset OCD or the OCD group as a whole were unrelated to the NPSR1 genotype. Based on our association finding relating NPSR1 genotype to early onset OCD, we suggest a differential role of the NPS system in OCD. In particular, the early onset OCD subtype seems to be characterized by a genetically driven low NPS tone, which might affect other OCD-related transmitter systems, including the serotonin and glutamate systems. In agreement with preclinical research, we suggest that NPS may be a promising pharmacological candidate with anti-obsessional properties.

Sustained incentive value of heroin-related cues in short- and long-term abstinent heroin users.

Models of addiction and addiction memory propose that drug-associated cues elicit incentive effects in drug users, which play an important role in maintenance of drug use and relapse. Incentive effects have been demonstrated for smoking and alcohol-related cues but evidence for heroin-related cues has been inconclusive. Furthermore, it is unknown whether appetitive effects of heroin-related cues persist after prolonged abstinence, although heroin addiction is known to have high relapse rates. Therefore, we investigated implicit and explicit valence of heroin-related cues in dependent users at different stages of abstinence using affective startle modulation. In Study I, 15 current heroin users were measured before and after detoxification. Correspondingly, 15 healthy control participants were tested twice at an interval of 14 days. In Study II, 14 long-term abstinent heroin users were additionally measured in a single session. Implicit processing of drug-related stimuli was assessed using affective startle modulation by pictures of heroin and smoking scenes. Explicit reactions were measured using ratings of valence and craving. In contrast to controls, heroin-dependent participants showed a clear reduction of startle response during heroin-related pictures (p<0.05). Detoxification did not significantly change their startle responses to heroin-cues. No difference between non-detoxified current and long-term abstinent heroin users was found in implicit reactions to heroin-cues, whereas explicit measures differed between both groups (all p<0.05). After detoxification and even after prolonged abstinence, heroin cues still exert implicit appetitive effects in heroin users. This implies that drug-induced adaptations of reward circuits are long-lasting, resulting in a highly stable addiction memory.

Investigation of tryptophan hydroxylase 2 (TPH2) in schizophrenia and in the response to antipsychotics.

Serotonergic transmission is considered relevant in the pathophysiology and the treatment of schizophrenia. Tryptophan hydroxylase (TPH) is the rate limiting enzyme in the biosynthesis of serotonin. While the TPH1 gene has been found to be associated with schizophrenia, studies focusing on TPH2 variants did not yield conclusive results for schizophrenia or the response to antipsychotic medication. We analyzed eleven TPH2 SNPs in two case-control samples consisting of 4453 individuals in total. Six SNPs were selected because of their potential functional relevance (rs4570625, rs11178997, rs11178998, rs7954758, rs7305115, and, rs4290270) and were supported by another 5 tagging SNPs selected based on HapMap LD information. In the discovery sample (1476 individuals), we observed a significant association with schizophrenia for rs10784941 (p = 0.009, OR minor G-allele 0.82 [0.71-0.95]) and rs4565946 (p = 0.011, OR minor T-allele 0.83 [0.71-0.96]). Association was also observed with a common rs4570625-rs4565946 haplotype (OR G-C haplotype 1.20 [1.02-1.40]; p = 0.0046). Single-marker associations could not be replicated in the replication sample consisting of 2977 individuals, but there was a strong trend regarding the rs4570625-rs4565946 G-C haplotype (OR 1.10 [0.98-1.24]; p(one-sided test) = 0.054). In smaller sub-samples, the rare rs4570625-rs4565946 T-T haplotype was associated with reduced processing speed (n = 193, p = 0.004) and sensorimotor gating (n = 68, p = 0.006) of schizophrenia patients. TPH2 variants and the rs4570625-rs4565946 G-C haplotype did not influence the beneficial response to antipsychotic drugs (n = 210) after four weeks of treatment administering the Positive and Negative Syndrome Scale of Schizophrenia (PANSS). We also investigated the association of the SNPs to treatment response, but did not get significant results. In sum, our results argue for only a minor role of TPH2 in schizophrenia.

A promoter variant of SHANK1 affects auditory working memory in schizophrenia patients and in subjects clinically at risk for psychosis.

Mutations in postsynaptic scaffolding genes contribute to autism, thus suggesting a role in pathological processes in neurodevelopment. Recently, two de novo mutations in SHANK3 were described in schizophrenia patients. In most cases, abnormal SHANK3 genotype was also accompanied by cognitive disruptions. The present study queries whether common SHANK variants may also contribute to neuropsychological dysfunctions in schizophrenia. We genotyped five common coding or promoter variants located in SHANK1, SHANK2 and SHANK3. A comprehensive test battery was used to assess neuropsychological functions in 199 schizophrenia patients and 206 healthy control subjects. In addition, an independent sample of 77 subjects at risk for psychosis was analyzed for replication of significant findings. We found the T allele of the SHANK1 promoter variant rs3810280 to lead to significantly impaired auditory working memory as assessed with digit span (12.5 ± 3.6 vs. 14.8 ± 4.1, P < .001) in schizophrenia cases, applying strict Bonferroni correction for multiple testing. This finding was replicated for forward digit span in the at-risk sample (7.1 ± 2.0 vs. 8.3 ± 2.0, P = .044). Previously, altered memory functions and reduced dendritic spines and postsynaptic density of excitatory synapses were reported in SHANK1 knock-out mice. Moreover, the atypical neuroleptic clozapine was found to increase SHANK1 density in rats. Our findings suggest a role of SHANK1 in working memory deficits in schizophrenia, which may arise from neurodevelopmental changes to prefrontal cortical areas.

The functional coding variant Asn107Ile of the neuropeptide S receptor gene (NPSR1) is associated with schizophrenia and modulates verbal memory and the acoustic startle response.

Recently, the neuropeptide S (NPS) neurotransmitter system has been identified as a promising psychopharmacological drug target given that NPS has shown anxiolytic-like and stress-reducing properties and memory-enhancing effects in rodent models. NPS binds to the G-protein-coupled receptor encoded by the neuropeptide S receptor gene (NPSR1). A functional variant within this gene leads to an amino-acid exchange (rs324981, Asn107Ile) resulting in a gain-of-function in the Ile107 variant which was recently associated with panic disorder in two independent studies. A potential psychopharmacological effect of NPS on schizophrenia psychopathology was demonstrated by showing that NPS can block NMDA antagonist-induced deficits in prepulse inhibition. We therefore explored a potential role of the NPSR1 Asn107Ile variation in schizophrenia. A case-control sample of 778 schizophrenia patients and 713 healthy control subjects was successfully genotyped for NPSR1 Asn107Ile. Verbal declarative memory and acoustic startle response were measured in subsamples of the schizophrenia patients. The case-control comparison revealed that the low-functioning NPSR1 Asn107 variant was significantly associated with schizophrenia (OR 1.19, p=0.017). Moreover, specifically decreased verbal memory consolidation was found in homozygous Asn107 carriers while memory acquisition was unaffected by NPSR1 genotype. The schizophrenia patients carrying the Ile107 variant demonstrated significantly reduced startle amplitudes but unaffected prepulse inhibition and habituation. The present study confirms findings from rodent models demonstrating an effect of NPS on memory consolidation and startle response in schizophrenia patients. Based on these findings, we consider NPS as a promising target for antipsychotic drug development.

The effects of combined acamprosate and integrative behaviour therapy in the outpatient treatment of alcohol dependence: a randomized controlled trial.

AIMS: The aim of this randomized, controlled, multisite trial was to evaluate the efficacy of combined treatment with integrative behaviour therapy (IBT) and acamprosate on drinking behaviour in detoxified alcohol-dependent patients. METHODS: A total of 371 patients were randomized to one of the three treatment conditions: IBT plus acamprosate, IBT plus placebo, or supportive counselling ('treatment as usual', TAU) plus acamprosate. The main outcome was success rate, i.e., rate of abstinence plus improvement according to the criteria of Feuerlein and Küfner (1989), at the end of the six-month treatment phase and at the subsequent six-month follow-up. Drinking status was validated by blood parameters (CDT, GGT, and MCV). Data were analyzed by an intent-to-treat model and missing data were classified as relapse. RESULTS: The success rates at the end of treatment under both TAU plus acamprosate (37.7%) and IBT plus placebo (48%) almost reached the levels derived from the literature. However, adding acamprosate to IBT did not result in the expected increase in success rate (IBT plus acamprosate: 47.6%), and success rates did not differ significantly between groups. Similarly, there was no significant difference between treatment success rates at follow-up. CONCLUSION: The results suggest that the combination of acamprosate and IBT is not more effective than treatment with either IBT or acamprosate alone. However, the two acamprosate conditions differed in success rate by about 10%, which might constitute a clinically relevant though statistically non-significant effect.

Novel schizophrenia risk gene TCF4 influences verbal learning and memory functioning in schizophrenia patients.

BACKGROUND: Recently, a role of the transcription factor 4 (TCF4) gene in schizophrenia has been reported in a large genome-wide association study. It has been hypothesized that TCF4 affects normal brain development and TCF4 has been related to different forms of neurodevelopmental disorders. Schizophrenia patients exhibit strong impairments of verbal declarative memory (VDM) functions. Thus, we hypothesized that the disease-associated C allele of the rs9960767 polymorphism of the TCF4 gene led to impaired VDM functioning in schizophrenia patients. METHOD: The TCF4 variant was genotyped in 401 schizophrenia patients. VDM functioning was measured using the Rey Auditory Verbal Learning Test (RAVLT). RESULTS: Carriers of the C allele were less impaired in recognition compared to those carrying the AA genotype (13.76 vs. 13.06; p = 0.049). Moreover, a trend toward higher scores in patients with the risk allele was found for delayed recall (10.24 vs. 9.41; p = 0.088). The TCF4 genotype did not influence intelligence or RAVLT immediate recall or total verbal learning. CONCLUSION: VDM function is influenced by the TCF4 gene in schizophrenia patients. However, the elevated risk for schizophrenia is not conferred by TCF4-mediated VDM impairment.

Influence of 5-HT3 receptor subunit genes HTR3A, HTR3B, HTR3C, HTR3D and HTR3E on treatment response to antipsychotics in schizophrenia.

OBJECTIVES: Among serotonin (5-HT) receptors, the 5-HT3 receptor is the only ligand-gated ion channel. 5-HT3 antagonists such as ondansetron and tropisetron may improve auditory gating and neurocognitive deficits in schizophrenic patients. Moreover, many antipsychotic drugs are antagonists at 5-HT3 receptors. However, the role of 5-HT3 receptor variants on response to antipsychotic drugs in schizophrenic patients is still unclear. METHODS: In a prospective, randomized, double-blind study, we have assessed six functional and coding variants of the subunit genes HTR3A, HTR3B as well as the novel HTR3C, HTR3D, and HTR3E subunits in the response to haloperidol or risperidone. Seventy patients were treated for 4 weeks and positive symptoms, negative symptoms, and general psychopathology were measured by the Positive and Negative Syndrome Scale (PANSS). RESULTS: HTR3E had an effect on the speed of response to antipsychotics. GG-allele carriers responded more quickly to treatment on the PANSS negative symptom subscale (P = 0.03) and on the total PANSS score (P = 0.04) irrespective of medication. In a second independent study of 144 schizophrenia patients treated with atypical antipsychotics, this effect could not be confirmed. CONCLUSION: Our findings argue against a major effect of HTR3 variants in response to antipsychotics. Solely, the HTR3E and also the HTR3A variant could exert a weak effect on the speed of response to antipsychotics.

Further evidence for a functional role of the glutamate receptor gene GRM3 in schizophrenia.

In recent years, evidence has been accumulating indicating a major role of glutamate in the pathogenesis and pathophysiology of schizophrenia. Of particular importance in this regard are the metabotropic glutamate receptors (GRM). Thus, a recently published trial of the amino acid analogue LY2140023, which exerts its effects through the activation of the glutamate receptors GRM3/GRM2, showed an improvement of positive and negative symptoms comparable to treatment with olanzapine. A functional variant of GRM3 has been described which modulates synaptic glutamate levels. We assessed whether this functional variant rs6465084 is related to schizophrenia in a large sample of patients and controls. We found an increased frequency of the A allele (p=0.027) and the AA genotype (p=0.024) in schizophrenia patients. Moreover, in an assessment of schizophrenia endophenotypes, patients of the AA genotype performed poorly in the digit symbol test, a measure of attention (p=0.008). Our results provide further evidence for the potential importance of the glutamate receptor GRM3 in schizophrenia, and indicate that the novel antipsychotic LY2140023 may actually be targeting a pathogenic pathway of schizophrenia.

The opioid peptides enkephalin and beta-endorphin in alcohol dependence.

BACKGROUND: Experimental evidence indicates that the endogenous opioid system influences stress responses as well as reinforces effects of addictive drugs. Because stress is an important factor contributing to drug dependence and relapse, we have now studied ethanol preference in enkephalin- and beta-endorphin-deficient mice under baseline conditions and after stress exposure. METHODS: In the present study we used a two-bottle choice paradigm to study ethanol consumption and stress-induced ethanol preference. To examine alcohol withdrawal symptoms the forced drinking procedure was employed. We performed an association analysis in two case-control samples of alcohol addicts to determine whether these opioid peptides also contribute to ethanol dependence in humans. RESULTS: Ethanol consumption was significantly reduced in the absence of beta-endorphins, particularly in female knockout animals. Stress exposure results in an increased ethanol consumption in wild-type mice but did not influence ethanol-drinking in beta-endorphin knockouts. Enkephalin-deficient mice showed no difference from wild-type mice in baseline ethanol preference but also showed no stress-induced elevation of ethanol consumption. Interestingly, we found a two-marker haplotype in the POMC gene that was associated with alcohol dependence in females in both cohorts. CONCLUSIONS: Together these results indicate a contribution of beta-endorphin to ethanol consumption and dependence.

Validity, reliability and objectivity of the family history method in psychiatry: a meta analysis.

BACKGROUND: The family history is a widely used method in psychiatry; but data on the method's objectivity, reliability and validity shows partly diverging results. METHOD: In October 2005, a Medline search was conducted that yielded 7 studies regarding objectivity/reliability and 13 studies regarding validity. Results for six main groups of psychiatric diagnoses and any mental disorder were combined qualitatively for objectivity/reliability, and quantitatively for validity. RESULTS: Objectivity was generally high (kappa in the 0.80 range). Reliability was high for any mental disorder, schizophrenia, substance abuse and depression (kappa in the 0.70 range), and low or medium for anxiety (kappa between 0.30 and 0.50). Results on validity displayed an OR=148 for the family history for schizophrenia; OR=64 for mania/bipolar disorder; and OR's between 8 and 194 for substance abuse, between 3 and 37 for depression, between 5 and 350 for personality disorders, between 2.5 and 49 for anxiety, and between 2.4 and 9 for any mental disorder. CONCLUSION: There is clear evidence that the family history provides results that are better than chance for all disorders examined. But variance among diagnostic groups and among studies is considerable.

The novel brain-specific tryptophan hydroxylase-2 gene in panic disorder.

Panic disorder is a common psychiatric disorder characterized by recurrent anxiety attacks and anticipatory anxiety. Due to the severity of the symptoms of the panic attacks and the frequent additional occurrence of agoraphobia, panic disorder is an often debilitating disease. Elevation of central serotonin levels by drugs such as clomipramine represents one of the most effective treatment options for panic disorder. This points to an important role of dysregulation of the serotonergic system in the genetic etiology of panic disorder. The novel brain-specific 5-HT synthesizing enzyme, tryptophan hydroxylase-2 (TPH2), which represents the rate-limiting enzyme of 5-HT production in the brain, may therefore be of particular importance in panic disorder. We focused on the putative transcriptional control region of TPH2 and identified two novel common single nucleotide polymorphisms (SNPs) of TPH2 in and close to this region. Moreover, a recently described loss-of-function mutation of TPH2 which results in an 80% reduction of serotonin production, was assessed. In an analysis of the putative transcriptional control region SNPs in a sample of panic disorder patients and controls no association of the disorder with the TPH2 SNPs or haplotypes was found. Moreover, the loss-of-function R441H mutation of TPH2 was not present in the panic disorder patients. The results of this first study of TPH2 in panic disorder argue against an importance of allelic variation of TPH2 in the pathogenesis of panic disorder with or without agoraphobia.

Association of DNA polymorphisms in the synaptic vesicular amine transporter gene (SLC18A2) with alcohol and nicotine dependence.

The brain synaptic vesicular amine transporter SLCA18A2 is a key component for the uptake of monoamines like dopamine or serotonin into vesicles. We have analyzed seven DNA polymorphisms located in the genomic region of SLC18A2 for association with alcohol- and nicotine dependence, using a family-based design. Our sample comprised 131 families with alcohol-dependent offspring and 96 families with at least one nicotine-dependent offspring. For the alcohol-dependent sample, we found statistical significant association for two single markers (rs363387, P=0.03; rs363333, P=0.0066) as well as for several haplotypes (minimal P=0.0038). When the sample with alcohol dependence was stratified according to gender, we observed increased association for the male subgroup (rs363387, P=0.0011). None of the markers showed association in the sample of families with nicotine dependence. However, analysis of a combined sample of alcohol and nicotine-dependent families resulted in single markers as well as several haplotypes showing statistical significant association with substance dependence (minimal P=0.0044). We conclude that DNA polymorphisms located in SLC18A2 might contribute to the development of substance dependence.

Norepinephrine transporter (NET) promoter and 5'-UTR polymorphisms: association analysis in panic disorder.

Several biochemical and pharmacological studies suggest that the catecholaminergic system involving the norepinephrine transporter (NET) is relevant for the pathogenesis of panic disorder. Three single nucleotide polymorphisms in the promoter or untranslated 5' region of the NET gene were investigated by means of RFLP analysis in a sample of 115 German patients with panic disorder and 115 matched controls. Statistical analysis failed to show association with the overall diagnosis of panic disorder. In the subgroup of patients with panic disorder without agoraphobia, however, two polymorphisms were found to be associated with the disease (G/C (rs2397771): p < 0.05; T/C (rs2242446): p < 0.01). While our data do not support a major function of the NET gene in the development of panic disorder, it may play a role in the subgroup of panic disorder without agoraphobia.

Association of specific haplotypes of D2 dopamine receptor gene with vulnerability to heroin dependence in 2 distinct populations.

CONTEXT: Dopamine receptor-mediated pathways play critical roles in the mechanism of addiction. However, associations of the D(2) dopamine receptor gene (DRD2) with substance abuse are controversial. OBJECTIVE: To determine whether susceptibility sites resided at DRD2. DESIGN: Haplotype-based case-control analysis of 2 distinct populations using 10 single nucleotide polymorphisms (SNPs) with heroin dependence. SETTING: Universities of Mainz and Bonn, Germany, and 3 local hospitals in southwestern China. Patients Cases and control subjects recruited from China (486 cases, 313 controls) and Germany (471 cases, 192 controls). INTERVENTIONS: Genotyping for 10 SNPs by 5'-exonuclease fluorescence assays. The D' value of linkage disequilibrium and haplotypes were generated by the expectation-maximization algorithm. MAIN OUTCOME MEASURES: Genotype, allele, and haplotype frequencies were compared between cases and controls by chi(2) tests constructed for each population. An additional 32 SNPs randomly distributed in the genome were genotyped for detecting population admixture in the 2 populations. RESULTS: A haplotype block of 25.8 kilobases (kb) was defined by 8 SNPs extending from SNP3 (TaqIB) at the 5' end to SNP10 site (TaqIA) located 10 kb distal to the 3' end of the gene. Within this block, specific haplotype cluster A (carrying TaqIB1 allele) was associated with a high risk of heroin dependence in Chinese patients (P = 1.425 x 10(-22); odds ratio, 52.80; 95% confidence interval, 7.290-382.5 for 8-SNP analysis). A putative recombination "hot spot" was found near SNP6 (intron 6 ins/del G), creating 2 new daughter haplotypes that were associated with a lower risk of heroin dependence in Germans (P = 1.94 x 10(-11) for 8-SNP analysis). There was no evidence of population stratification in either population. CONCLUSIONS: These results strongly support a role of DRD2 as a susceptibility gene with heroin dependence in Chinese patients and was associated with low risk of heroin dependence in Germans.

Association of the functional V158M catechol-O-methyl-transferase polymorphism with panic disorder in women.

Panic disorder is an anxiety disorder with an estimated heritability of up to 48%. Pharmacological and genetic studies suggest that genes coding for proteins involved in the catecholaminergic system might be relevant for the pathogenesis of the disease. In the present study, we genotyped a single nucleotide polymorphism (472G/A=V158M) in the coding region of the catechol-O-methyl-transferase (COMT) gene in 115 patients with panic disorder and age- and sex-matched controls. Association analysis revealed a significant excess of the more active COMT allele (472G=V158) in patients with panic disorder (p=0.04), particularly in female patients (p=0.01), but not in male patients (p=1.0). The assessment of a possible interaction of the COMT polymorphism with a previously reported functional 30-bp VNTR in the monoamine oxidase A promoter (MAOALPR) in female patients did not yield significant results. Our data support a role of the 472G/A (V158M) COMT polymorphism or a nearby locus in the pathogenesis of panic disorder in women.

Association of a functional 1019C>G 5-HT1A receptor gene polymorphism with panic disorder with agoraphobia.

Panic disorder is a common anxiety disorder which frequently co-occurs with agoraphobia. A functional promoter polymorphism in the serotonin receptor 1A (5-HT1A) gene has been found to be associated with major depression as well as anxiety- and depression-related personality traits. We investigated a possible association between this 5-HT1A gene promoter polymorphism and panic disorder by genotyping the 1019C>G single nucleotide polymorphism in 134 panic-disorder patients with and without agoraphobia and matched 134 controls. In our sample no significant evidence of allelic association in the combined panic-disorder group was found. However, our results show a significant association with the G allele in patients with panic disorder with agoraphobia (p=0.03, n=101). In conclusion, our findings do not support a major contribution of this polymorphism to the pathogenesis of panic disorder, but provide evidence for a possible role in the subgroup with agoraphobia.

No evidence for DUP25 in patients with panic disorder using a quantitative real-time PCR approach.

A duplication of chromosome 15q24-q26 (DUP25) has been reported to be associated with anxiety disorders. We tested for the presence of DUP25 in a sample of 50 patients with panic disorder and 50 controls using a quantitative real-time PCR approach. Contrary to the original finding, our results were compatible with the absence of DUP25, and no significant difference could be detected between patients and controls ( P=1.0). Thus, our study does not support the hypothesis of an involvement of DUP25 in panic disorder.